Light Modulates Important Pathogenic Determinants and Virulence in ESKAPE Pathogens Acinetobacter baumannii, Pseudomonas aeruginosa, and Staphylococcus aureus.

Light sensing has been extensively characterized in the human pathogen Acinetobacter baumannii at environmental temperatures. However, the influence of light on the physiology and pathogenicity of human bacterial pathogens at temperatures found in warm-blooded hosts is still poorly understand. In this work, we show that Staphylococcus aureus, Acinetobacter baumannii, and Pseudomonas aeruginosa (ESKAPE) priority pathogens, which have been recognized by the WHO and the CDC as critical, can also sense and respond to light at temperatures found in human hosts. Most interestingly, in these pathogens, light modulates important pathogenicity determinants as well as virulence in an epithelial infection model, which could have implications in human infections. In fact, we found that alpha-toxin-dependent hemolysis, motility, and growth under iron-deprived conditions are modulated by light in S. aureus Light also regulates persistence, metabolism, and the ability to kill competitors in some of these microorganisms. Finally, light exerts a profound effect on the virulence of these pathogens in an epithelial infection model, although the response is not the same in the different species; virulence was enhanced by light in A. baumannii and S. aureus, while in A. nosocomialis and P. aeruginosa it was reduced. Neither the BlsA photoreceptor nor the type VI secretion system (T6SS) is involved in virulence modulation by light in A. baumannii Overall, this fundamental knowledge highlights the potential use of light to control pathogen virulence, either directly or by manipulating the light regulatory switch toward the lowest virulence/persistence configuration.IMPORTANCE Pathogenic bacteria are microorganisms capable of producing disease. Dangerous bacterial pathogens, such as Staphylococcus aureus, Pseudomonas aeruginosa, and Acinetobacter baumannii, are responsible for serious intrahospital and community infections in humans. Therapeutics is often complicated due to resistance to multiple antibiotics, rendering them ineffective. In this work, we show that these pathogens sense natural light and respond to it by modulating aspects related to their ability to cause disease; in the presence of light, some of them become more aggressive, while others show an opposite response. Overall, we provide new understanding on the behavior of these pathogens, which could contribute to the control of infections caused by them. Since the response is distributed in diverse pathogens, this notion could prove a general concept.

The crystal structure of the malic enzyme from Candidatus Phytoplasma reveals the minimal structural determinants for a malic enzyme.

Phytoplasmas are wall-less phytopathogenic bacteria that produce devastating effects in a wide variety of plants. Reductive evolution has shaped their genome, with the loss of many genes, limiting their metabolic capacities. Owing to the high concentration of C4 compounds in plants, and the presence of malic enzyme (ME) in all phytoplasma genomes so far sequenced, the oxidative decarboxylation of L-malate might represent an adaptation to generate energy. Aster yellows witches'-broom (Candidatus Phytoplasma) ME (AYWB-ME) is one of the smallest of all characterized MEs, yet retains full enzymatic activity. Here, the crystal structure of AYWB-ME is reported, revealing a unique fold that differs from those of `canonical' MEs. AYWB-ME is organized as a dimeric species formed by intertwining of the N-terminal domains of the protomers. As a consequence of such structural differences, key catalytic residues such as Tyr36 are positioned in the active site of each protomer but are provided by the other protomer of the dimer. A Tyr36Ala mutation abolishes the catalytic activity, indicating the key importance of this residue in the catalytic process but not in the dimeric assembly. Phylogenetic analyses suggest that larger MEs (large-subunit or chimeric MEs) might have evolved from this type of smaller scaffold by gaining small sequence cassettes or an entire functional domain. The Candidatus Phytoplasma AYWB-ME structure showcases a novel minimal structure design comprising a fully functional active site, making this enzyme an attractive starting point for rational genetic design.

Oral Thrombus: Report of 122 cases with clinically descriptive data.

BACKGROUND: The aim of the present study was to assess the frequency and characterize clinic-pathologic aspects of thrombus occurring as a single lesion or in association with other oral pathologies. MATERIAL AND METHODS: 122 cases of thrombus from the oral cavity were retrieved. Information regarding site of the lesion, age, sex and clinical diagnosis or hypothesis and associated lesions were collected from the patients' records. RESULTS: The lesions occurred in a wide age range but the 5th decade was the most prevalent and female patients were more affected. The most frequent site for the lesion was the lip, followed by tongue, buccal mucosa, alveolar ridge, gingiva, floor of the mouth and vestibule. Thirty-five cases were associated with other vascular anomalies or actinic cheilitis. Microscopically, typical thrombus morphology was present. Organized thrombus presented neovascularization and fibroblasts, associated with hemorrhagic areas. CONCLUSIONS: Only 4 cases of oral thrombus have been described in the oral cavity. Given the limited number of cases reported, the importance of a thrombus in the oral cavity is not well established. This study contributes to establishing the profile of patients presenting oral thrombus, a lesion not rare but not well documented.

Extra-tongue oral granular cell tumor: Histological and immunohistochemical aspect.

BACKGROUND: Granular cell tumor (GCT) is an uncommon benign tumor founded in any part of the body but mainly in the tongue. Extra-tongue oral granular cell tumor (ETOGCT) is rare with few cases reported. Here we describe seven cases of oral GCT located in sites other then the tongue and discuss histopathological and immunohistochemical differences between differential diagnoses. MATERIAL AND METHODS: We retrieved all cases diagnosed with oral granular cell tumor, from the Oral Pathology Service at the School of Dentistry/ University of São Paulo, and excluded the ones sited in the tongue. Immunohistochemical staining anti-S100 was also performed. RESULTS: The presented cases of Extra-tongue Oral Granular Cell Tumor (ETOGT) are composed by granular cells with intimately association with the adjacent tissue. Atypia and mitoses were not seen, and in most cases, the typical pseudoepitheliomatous hyperplasia was not observed. CONCLUSIONS: The importance of an adequate attention is to avoid misdiagnoses, since ETOGT is rare and the tricking histopathological findings could induce to it. All the cases can be differentiated from the tumors that has a granular cell proliferation through a morphological analysis and when needed, immunohistochemistry stain.

Hydroxyapatite Growth Inhibition Effect of Pellicle Statherin Peptides.

In our recent studies, we have shown that in vivo-acquired enamel pellicle is a sophisticated biological structure containing a significant portion of naturally occurring salivary peptides. From a functional aspect, the identification of peptides in the acquired enamel pellicle is of interest because many salivary proteins exhibit functional domains that maintain the activities of the native protein. Among the in vivo-acquired enamel pellicle peptides that have been newly identified, 5 peptides are derived from statherin. Here, we assessed the ability of these statherin pellicle peptides to inhibit hydroxyapatite crystal growth. In addition, atomistic molecular dynamics (MD) simulations were performed to better understand the underlying physical mechanisms of hydroxyapatite growth inhibition. A microplate colorimetric assay was used to quantify hydroxyapatite growth. Statherin protein, 5 statherin-derived peptides, and a peptide lacking phosphate at residues 2 and 3 were analyzed. Statherin peptide phosphorylated on residues 2 and 3 indicated a significant inhibitory effect when compared with the 5 other peptides (P < 0.05). MD simulations showed a strong affinity and fast adsorption to hydroxyapatite for phosphopeptides, whereas unphosphorylated peptides interacted weakly with the hydroxyapatite. Our data suggest that the presence of a covalently linked phosphate group (at residues 2 and 3) in statherin peptides modulates the effect of hydroxyapatite growth inhibition. This study provides a mechanism to account for the composition and function of acquired enamel pellicle statherin peptides that will contribute as a base for the development of biologically stable and functional synthetic peptides for therapeutic use against dental caries and/or periodontal disease.

The impact of stannous, fluoride ions and its combination on enamel pellicle proteome and dental erosion prevention.

OBJECTIVES: To compare the effects of stannous (Sn) and fluoride (F) ions and their combination on acquired enamel pellicle (AEP) protein composition (proteome experiment), and protection against dental erosion (functional experiment). METHODS: In the proteome experiment, bovine enamel specimens were incubated in whole saliva supernatant for 24h for AEP formation. They were randomly assigned to 4 groups (n=10), according to the rinse treatment: Sn (800ppm/6.7mM, SnCl2), F (225ppm/13mM, NaF), Sn and F combination (Sn+F) and deionized water (DIW, negative control). The specimens were immersed 3× in the test rinses for 2min, 2h apart. Pellicles were collected, digested, and analyzed for protein content using liquid chromatography electrospray ionization tandem mass spectrometry. In the functional experiment, bovine enamel specimens (n=10) were similarly treated for pellicle formation. Then, they were subjected to a five-day erosion cycling model, consisting of 5min erosive challenges (15.6 mM citric acid, pH 2.6, 6×/d) and 2min treatment with the rinses containing Sn, F or Sn+F (3×/d). Between the treatments, all specimens were incubated in whole saliva supernatant. Surface loss was determined by profilometry. RESULTS: Our proteome approach on bovine enamel identified 72 proteins that were common to all groups. AEP of enamel treated with Sn+F demonstrated higher abundance for most of the identified proteins than the other groups. The functional experiment showed reduction of enamel surface loss for Sn+F (89%), Sn (67%) and F (42%) compared to DIW (all significantly different, p<0.05). CONCLUSION: This study highlighted that anti-erosion rinses (e.g. Sn+F) can modify quantitatively and qualitatively the AEP formed on bovine enamel. Moreover, our study demonstrated a combinatory effect that amplified the anti-erosive protection on tooth surface.

A Health Technology Assessment: laparoscopy versus colpoceliotomy.

INTRODUCTION: The objective of this paper is the comparison between two different technologies used for the removal of a uterine myoma, a frequent benign tumor: the standard technology currently used, laparoscopy, and an innovative one, colpoceliotomy. It was considered relevant to evaluate the real and the potential effects of the two technologies implementation and, in addition, the consequences that the introduction or exclusion of the innovative technology would have for both the National Health System (NHS) and the entire community. METHODS: The comparison between these two different technologies, the standard and the innovative one, was conducted using a Health Technology Assessment (HTA). In particular, in order to analyse their differences, a multi-dimensional approach was considered: effectiveness, costs and budget impact analysis data were collected, applying different instruments, such as the Activity Based Costing methodology (ABC), the Cost-Effectiveness Analysis (CEA) and the Budget Impact Analysis (BIA). Organisational, equity and social impact were also evaluated. RESULTS: The results showed that the introduction of colpoceliotomy would provide significant economic savings to the Regional and National Health Service; in particular, a saving of € 453.27 for each surgical procedure. DISCUSSION: The introduction of the innovative technology, colpoceliotomy, could be considered a valuable tool; one offering many advantages related to less invasiveness and a shorter surgical procedure than the standard technology currently used (laparoscopy).

Efeitos clínicos e microbiológicos do óleo de copaíba (copaifera officinalis) sobre bactérias formadoras de placa dental em cães / Clinical and microbiological effects of copaiba oil (copaifera officinalis) on dental plaque forming bacteria in dogs

O potencial de uso do óleo de copaíba (Copaifera officinalis) na prevenção da doença periodontal, eliminando seu agente etiológico, foi avaliado em 18 cães sem raça definida, distribuídos homogeneamente em três grupos: teste, (contendo óleo de copaíba) controle positivo e controle negativo. Os tratamentos ocorreram três vezes ao dia, durante oito dias. Ao nono dia, os animais receberam aplicação tópica de fucsina básica 0,5 por cento para evidenciação do biofilme. Mudanças na halitose e gengivite foram avaliadas diariamente por inspeção visual. Adicionalmente, foram realizados testes laboratoriais de inibição de aderência de Streptococcus mutans e ensaio antimicrobiano de difusão em ágar, sobre bactérias formadoras de placa dental. Os resultados da placa evidenciada apontaram áreas de cobertura microbiana nos dentes de 53,4±8,8 por cento, 28,5±5,4 por cento, e 22,3±5,3 por cento para os grupos negativo, positivo e teste, respectivamente, indicando diferença entre o controle negativo e os demais grupos (P<0,05). Quanto à melhora nos aspectos clínicos, halitose e gengivite, o grupo teste respondeu melhor quando comparado ao grupo controle negativo (P<0,05). A análise dos ensaios de difusão e inibição de aderência mostrou superioridade do grupo da copaíba (teste) em relação aos outros grupos (P<0,05). Os resultados sugerem o uso do óleo de copaíba na prevenção da doença periodontal e como um possível substituto da clorexidina na terapia antimicrobiana oral.

The copaiba oil (Copaifera officinalis) potential was evaluated in preventing periodontal disease and reducing its etiology. For that 18 mongrel dogs were homogeneously distributed in three groups: test (copaiba oil), positive control (chlorexidine) and negative control. The treatments were carried out three times a day, during eight days. On the 9th day, the animals were tested with a 0.5 percent basic solution of fuchsin for the detection of biofilm. Changes in halitosis and gingivitis were daily observed. In addition, the following laboratory tests were done: inhibition of the adherence of Streptococcus mutans, and plaque forming bacteria antimicrobial assays by the agar diffusion method. The results of the fuchsin test showed that dental plaque reached areas of 53.4±8.8 percent, 28.5±5.4 percent, and 22.3±5.3 percent in the negative control, positive control, and test groups, respectively, showing differences between dogs from the negative control group and dogs from the other two groups (P<0.05). Furthermore, halitosis and gingivitis decreased in the copaiba group animals when compared with the negative group (P<0.05). The results of the attachment inhibition and agar diffusion tests showed that copaiba induced better effects against the microorganisms as compared to the results of the other groups (P<0.05). These findings suggest that copaiba oil may effectively replace chlorexidine for oral antimicrobial therapy and prevention of periodontal disease.

Emergence of Pseudomonas aeruginosa strains producing metallo-beta-lactamases of the IMP-15 and VIM-2 types in Mexico.

Eighty-six carbapenem non-susceptible Pseudomonas aeruginosa isolates collected in the National Institute of Respiratory Diseases of Mexico City were screened for the presence of metallo-beta-lactamase (MBL) activity using both E-test strips and a microbiological assay with EDTA-imipenem. Genomic comparisons and sequence analyses conducted with these isolates revealed the presence of bla(VIM-2) in two clonally related isolates, and bla(IMP-15) in a clonally unrelated isolate. Both genes were found to be carried by class 1 integrons, and bla(IMP-15) was additionally present on a broad host-range plasmid. This is the first report of co-existing P. aeruginosa strains producing different MBLs in a Mexican hospital, highlighting the necessity of appropriate surveillance to prevent dissemination of carbapenem resistance.

Amyloid precursor protein in platelets: a peripheral marker for the diagnosis of sporadic AD.

BACKGROUND: An altered pattern of amyloid precursor protein (APP) forms consisting in a reduced ratio between the upper (130 kDa) and the lower (106 to 110 kDa) immunoreactivity bands has been described in platelets of patients with AD. OBJECTIVE: To evaluate the sensitivity and the specificity of platelet APP forms' ratio (APPr) as a marker for AD. METHODS: Eighty-five patients with probable AD and 95 control subjects (CON), including healthy individuals and neurologic patients, entered the study. Platelet APPr was evaluated by means of Western Blot analysis and immunostaining in the whole platelet homogenate, and calculated by the ratio between the optical density (OD) of the upper (130 kDa) and the lower (106 to 110 kDa) APP immunoreactive bands. RESULTS: Mean APPr levels were decreased in AD patients (mean OD +/- SD = 0.35 +/- 0.18) compared with the CON group (mean OD +/- SD = 0.92 +/- 0.38) (DF 1, 178, p < 0.0001). Accuracy levels measured by Receiver Operating Curve analysis showed that a cut-off level of 0.57 resulted in a sensitivity of 88.2% and a specificity of 89.4%, with an area under the curve of 0.945. APPr levels were significantly associated with disease severity (mild AD versus moderate AD: p < 0.0001; moderate AD versus severe AD: p < 0.05). CONCLUSION: Platelet APPr allowed to differentiate AD from normal aging and other dementing disorders with high sensitivity and specificity. These findings suggest that platelet APPr may be of help as an adjunctive diagnostic tool in clinical practice.

[Coronary atherectomy using the transluminal endarterectomy extraction catheter. Initial experience]. / Aterectomia coronária com o uso do cateter de endarterectomia por extração transluminal. Experiência inicial.

PURPOSE: To describe a new alternative technique for treating coronary artery disease: the coronary atherectomy with the transluminal endarterectomy-extraction catheter. METHODS: Four patients, 1 female and 3 males age 46 to 65 years (mean 53 +/- 8.5 years), were submitted to coronary atherectomy with the transluminal endarterectomy-extraction catheter. One patient presenting stable angina, one presenting recent angina, one with residual stenosis after acute myocardial infarction treated with intravenous streptokinase and one with two episodes of syncope and ECG alterations. The treated arteries were: left anterior descending in 3 patients and left circumflex in one. Two lesion were concentric and two were segmentary and eccentric. RESULTS: The coronary artery stenosis ranged from 80 to 95% (mean of 90 +/- 7.1%) before the atherectomy and from 20-50% (mean of 32.5 +/- 12.6%) after the atherectomy. Except the first patient, the other 3 were discharged in less than 48 hours after the atherectomy. None presented chest pain during the procedure and in three of them were no recordings of dissection or coronary artery perforation. In one patient the treated artery presented total occlusion (thrombus) 15 minutes after the procedure, but was immediate and successfully reopened with balloon angioplasty. CONCLUSION: Coronary atherectomy with the "transluminal endarterectomy-extraction catheter" has shown to be a safe and feasible procedure and to bring satisfactory immediate results.

A case of chondrodystrophic dwarfism in the Italian late Upper Paleolithic.

During excavations by P. Graziosi at Romito Cave near Papasidero (Cosenza) in Calabria, Italy, two skeletons (Romito 1 and 2) were discovered in a common grave. Although the specimens were briefly described by Messeri (Atti X Riuniuone Scientifica Ist. Ital. Preist. Protost., pp. 301-307, 1966), it is generally unknown in the anthropological literature that one of these individuals is a chondrodystrophic dwarf. As such, the specimen provides the earliest known case of dwarfism in the human skeletal record, extending the time span of this genetically determined growth abnormality to approximately 10,000 years ago. The specimen (Romito 2) exhibits features typical of chondrodysplasia, including a high domed skull, compressed cranial base, and in the postcranial skeleton extremely shortened diaphyseal lengths. The unique combination of these features suggests this pathological condition is acromesomelic dysplasia. Besides providing evidence for a greater antiquity of dwarfism than previously known, the fact that this individual reached late adolescence attests to tolerance of Upper Paleolithic groups for severely abnormal individuals and their ability to support members who were of limited economic value to the social group.

Dwarfism in an adolescent from the Italian late Upper Palaeolithic.

There have been numerous reports of pathological conditions in the hominid fossils, but these have only involved trauma or age-related deterioration in the health of otherwise normal individuals. Here we describe a skeleton of a young male from Riparo del Romito in Calabria, dated to the Epi-Gravettian of southern Italy. The preserved skeletal elements show that this individual (Romito 2) had the skull and long-bone morphology consistent with a mesomelic form of dwarfism, most probably the autosomal recessive disorder acromesomelic dysplasia. Generally recognized at birth, persons with acromesomelic dysplasia usually have normal intelligence and are free of serious medical problems. However, growth deficiency is severe (adult height typically is 110-120 cm) and mobility at the elbows is restricted. These physical impairments would have greatly interfered with the individual's participation in subsistence activities and would have been a substantial handicap in a nomadic hunting and gathering group. Thus, besides being the earliest known case of dwarfism in the human record, this skeleton provides evidence of tolerance of, and care for, a severely deformed individual in the Palaeolithic.